Rotary disc cutter heads with core breaking devices for continuous miners



June 7, 1955 Filed July 9, 1952 F. CARTLIDGE ROTARY DISC CUTTER HEADSWITH CORE BREAKING DEVICES FOR CONTINUOUS MINERS 4 Sheets-Sheet 1 Invenfar j/diZ/i Carl/[aye 'jnvenfor Q. M flfzarney June 1955 F. CARTLIDGEROTARY DISC CUTTER HEADS WITH CORE BREAKING DEVICES FOR CONTINUOUSMINERS Filed July 9, 1952 4 Sheets-Sheet 2 June 7, 1955 F. CARTLIDGEROTARY DISC CUTTER HEADS WITH CORE BREAKING Filed July 9, 1952 4Sheets-Sheet 3 20 1 Q 3/ i 20 .9/ 30 f 53 i! T 303/ fi i i 52 I .54 1!!20 20 '1 5a A 8| 0 I I 3 /6 20 i 6 l 20 war 20 S 55 4 I 'V/0 1 b 20 8/54: 1| I6 1 I l 20 l 60 .5 20 4 I a 2: I l w WW l 59"" j/ I 10 fl a x LL l g Invewzar Franz? Car/[26 29% a: W

June 7, 1955 F. CARTLIDGE 2,710,179

ROTARY DISC CUTTER HEADS WITH GORE BREAKING DEVICES FOR CONTINUOUSMINERS Filed July 9, 1952 4 Sheets-Sheet 4 T 5 4 I 26 E 6 6 i XX? 16 25v fig 3/ Invenzor I6 I .97 25 20 Fran/F ('arf/z d e Unite This inventionrelates to improvements in cutter heads for coal mining machines, andmore particularly to core breakers used with such devices. The inventionis especially advantageous with cutter heads of the rotary disc typeused in continuous mining machines but is not lim ited to such use.

One of the principal problems involved in the development of rotary disccutter heads for continuous miners is that of obtaining a greaterproportion of relatively large coal lumps as compared to fines usuallyobtained by such machines. One of the principal methods heretoforeemployed for this purpose is that of attacking the coal face with aplurality of rotating cutters carried by cutter discs or cutter chains,or a combination of both, which cutters are spaced apart a substantialdistance to cut kerfs leaving relatively wide cores therebetween, to bebroken out by core breakers also carried by the rotating cutters. Thecuttings resulting from cutting the several kerfs must necessarilyproduce a substantial proportion of fines, but it has been contemplatedthat the cores can be broken out and removed in larger lumps so as toraise the average size of lump coal loaded out by the machine. Manyforms and arrangements of breaker devices have heretofore been employedwhich should, in theory, produce a large proportion of lump coal fromthe cores, but, in practice, much of such lump coal is reduced to fineswhile it is being removed from the working face.

I have ascertained that most of the difficulty above referred to is dueto the fact that fragmented coal requires approximately two times thevolumetric space that it occupies in the solid state, and that breakerdevices of the kind heretofore employed do not allow for adequateexpansion of the fragmented coal. As a result, the larger lumps tend tobecome crushed by and between moving parts of the cutter head and thesolid face before they are discharged from adjacent the face.

The principal object of the present invention is to provide an improvedform of wedge-like core breakers fixed head constructed in accordancewith my invention;

Figure 2 is a side view of the parts shown in Figure 1;

Figure 3 is a detailed section taken on line 3-3 of Figure 1.

Figure 4 "is an enlarged fragmentary detail view in perspective of thecutter head drum, showing three of the cutter discs with theirrespective breaker wedges mounted thereon, but with the cutter bitsremoved from the discs;

Figure 5 is a detail perspective view of one of the breaker wedges;

Figure 6 is a detail section taken generally along planes States PatentPatented June '7, i hfi indicated by line 66 of Figure 4, to illustratehow each of the wedges progressively breaks off its adjacent core anddirects the lumps through an opening in the periphery of the proximatecutter disc into the kerf which has been cut by said disc;

Figure 7 is a detail section taken on line 7--7 of Figure 4, showing thewedges still farther advanced than in Figure 6;

Figure 8 is a detail section taken on line 8-8 of Figure 4, showing thewedges still farther advanced than in Figure 7;

Figure 9 is a schematic diagram illustrating the transfer action of thewedge as viewed generally toward the periphery of the cutter discs.

Referring now to the embodiment of my invention illustrated in thedrawings, Figure 1 shows the front part of a cutter head for acontinuous mining machine of the kind broadly disclosed in my copendingapplication bearing Serial Number 116,684, filed September 20, 1949,wherein a cutter frame is pivotally connected at its rear end forvertical pivotal swinging movement relative to the main frame of themining machine, with a rotary disc type cutter head rotatable on atransverse axis at the front end of said cutter frame.

The cutter frame shown herein includes side frame members 11, 11 withthe cutter head 12 rotatably supported on suitable bearingstherebetween. The cutter frame is raised or lowered by any suitablepower means (not shown) during the cutting operation.

The rotary head 12 has a hollow drum 15 extending the length thereof,with a plurality of generally similar radially extending kerf-cuttingdiscs 16, 16 fixed in axially spaced relation therealong. Each of saidkerf-cutting discs is provided with a plurality of radially projectingbit holding blocks 20, 20 at widely spaced equal angles around itsperiphery. Said bit holding blocks are wider than their respective discsand, as usual, are arranged to receive cutter bits 21, 21 disposed atvarying angles to the plane of said disc, so that the discs cut severalhorizontally spaced kerfs in the coal, as indicated at 25, 25 in Figure1, in advance of the machine, when the cutter head is swung vertically,and the cutter discs are rotated. A standing core 26 is left betweeneach adjacent pair of cutter discs. The bit blocks 20, 20 projectradially beyond the concentric edges 30, 36 of the cutting discs 16 toleave open spaces 31, 31 between each adjacent pair of said bit blocks.

The cutter head may be driven as usual through a pair of cutter chains35, 35 guided for orbital movement along the side frame members 11, andtrained about sprockets 36, 36 fixed to the outer ends of the rotaryhead. The sprocket teeth 40 engage recesses 41 in the under faces of thecutter blocks 42 of the cutter chain. The cutter blocks are pivotallyconnected together as usual by links 43, and cutter bits 44 are mountedin said cutter blocks at several angles to the orbital plane of thecutter chains, to cut vertical kerfs 45 at opposite ends of the cutterhead substantially similar to the intermediate kerfs 25 cut by thecutter discs, as indicated in Figure 1, excepting that the end kerfs 45may be formed somewhat wider than the intermediate kerfs.

In the illustrative form shown herein, each of the cutter discs has sixbit blocks 20, spaced circumferentially thereabout at equal distances,with said bit holders arranged to support their bits in three successiveangular positions; that is to say, one in the center, the next towardone side, and the next toward the other side of the disc. The cutterchains 35 are longer than the circumference of the discs, so may eachhave a larger number of cutter blocks 42 with cutter bits 44 having morethan three angular bit positions, if desired.

The novel core breaking means of my present invention consists of aplurality of generally wedge-shaped plates 50, which for convenienceherein may be referred to as wedges. The shape of the wedges is bestshown in Figures 3 to 7, wherein it will be noted that in fiatwise vieweach wedge is similar to a sector of an annulus, with its inclined corebreaking surface A defined by a leading edge 51, a lagging edge 52, aradially outer arcuate edge 53, and a radially inner arcuate edge 54.The leading edge 51 and the radially outer edge 53 are of substantiallyuniform thickness the radially inner edge 54 increases gradually fromthe leading edge 51 to the lagging edge 52. Since the plate is longestin a direction circumferential of the disc 16 on which it is carried,the lagging edge 52 increases in thickness from the radially outer edge53 to the radially inner edge 54 at a relatively sharp angle. The corebreaking face A is also slightly concave both lengthwise and radiallythereof, to present a substantially plowlike surface in a generallyhelical outwardly inclined angle with respect to the axis of the drum,as indicated in the several figures.

Each of the cutter discs 16 has a wedge fixed at one side thereof withits radially inner edge 54 closely adjacent the periphery of the drumand its radially outer edge 53 substantially coincident with theadjacent arcuate edge 30 of the disc. Each of said wedges preferablyextends through an arc slightly greater than that of the open space 31between adjacentbit blocks 20, so that the radial outer edge 53 of thewedge is nested at both its front and rear ends beneath the laterallyoverhanging bit blocks.

Each wedge is fixed to its disc by suitable means, such as by aplurality of positioning studs 58, herein three in number, screwed intothe rear face of the wedge, with their inner ends fitting in apertures59 in the disc. The studs have nuts 60 on their opposite ends, holdingsaid wedges to the disc.

Referring to Figure 9, it will be observed that each wedge St is mountedon its respective disc so that the lagging edge 52 of its core breakingsurface is positioned directly opposite and substantially in alignmentradially and axially with an open space 31 between two bit blocks 20, 20on the periphery of the next adjacent cutter disc, and approximatelymidway between said bit blocks.

In the illustrative form shown, the bit blocks on one disc are offsetcircumferentially from the bit blocks of the next adjacent disc as iscommon practice, so that all the cutter bits of the several discs do notimpinge upon the coal face at the same time. Accordingly the wedges 50,50 are offset correspondingly on their respective discs to maintain thedesired axial relationship between the wedge and the circumferentialopening 31 of the opposite disc, as described in the foregoingparagraph, to produce the novel transfer effect as will now be describedin connection with Figures 6 to 9.

Figure 6 is a section taken diametrically through the edge of twoadjacent cutter discs, showing the kerfs 25, cut thereby, and with astanding core of coal 2-6 therebetween, before said core is engaged bythe break ing wedges.

Figure 7 is a section showing the position in which the discs have beenrotated so that the wedge begins to engage one corner of the core 26 tobreak off the top portion thereof. It will be observed that the wedgeface is disposed at such an outwardly inclined angle to the nextadjacent disc that, as the coal is broken from the outer end of thecore, it tends to be directed at an angle normal to the wedge, andtoward the open space 31 between the bit blocks of the next adjacentdisc, and thence into the kerf 25 already cut by the bits of the latterdisc. For convenience in description, this open space 31 formed in thekerf 25 between each adjacent pair of bit blocks 20 may be termed thematerial access way.

Figure 8 shows the manner in which, upon further rotation, the wedge 50breaks off more coal from the standing core, and simultaneously directsthe lumps into the material access way of the next adjacent cutter disc,so that the resulting lumps are transferred into the relatively largearea formed by said material access way of the adjacent or second disc,together with the kerf 25 already cut by the latter. From this position,the lumps are removed from the kerf by the paddle-like front faces ofthe cutter blocks 20 of the second cutter disc.

Figure 9 also indicates graphically how the plowlike face of a wedgeserves to transfer the coal lumps laterally in a positively directedstream into the material access way of the adjacent cutter disc, so asto permit clearance of the lumps from the coal face with a minimum ofcrushing.

Clearance of the larger lumps from each material access way, and thekerf in which the disc is operating, is aided by the fact that much ofthe coal cut by the cutter bits 21 and 44 from intermediate kerfs 25 andend kerfs, respectively, are in the form of relatively fine cuttings,which tend to fall by gravity out of said kerfs, thus leaving more spacefor the lump coal.

The wedge principle above described can be applied to a wide variety ofcutter head structures and is not necessarily limited to a cutter headrotating on a horizontal axis. The illustrative embodiment shown inFigure 1 shows the invention as applied to a S-disc cutter head. In thisform of cutter head, the center disc is provided with two similar wedges50, 50a, one on each side thereof, and fixed diametrically opposite toeach other. The two discs on each side of the center disc are eachprovided with one outwardly facing wedge. The wedges on the next twodiscs direct the fragmented lumps into the material access way formed bythe adjacent cutter chains 35. This arrangement of two opposed sets ofwedges serves to balance the reaction of the several wedges axially ofthe cutter head while breaking the cores in opposed directions.

Although I have shown and described certain embodiments of my invention,it will be understood that I do not wish to be limited to the exactconstruction shown and described, but that various changes andmodifications may be made without departing from the spirit and scope ofthe invention as defined in the appended claims.

I claim.

1. In a cutting and dislodging head for a continuous mining machine, arotatable drum having a plurality of axially spaced discs, each dischaving a plurality of circumferentially spaced bit carrying cutterblocks extending radially outwardly from the periphery thereof forcutting spaced parallel kerfs with outstanding cores therebetween, theopen spaces between the blocks forming material access ways, corebreaking wedges supported at the sides of certain of said discs, theouter surface of each of said wedges being disposed in a generallyhelical outwardly inclined angle with respect to the drum access, andthe lagging edge portion of each of said wedges being substantially inalignment radially and axially with a material access way in theadjacent disc to break and move portions of the intermediate core intosaid material access way for removal by the cutter blocks on saidadjacent disc.

2. The combination of claim 1 wherein each wedge extends radially fromthe drum substantially to the edge of a material access Way on itsrespective disc, and is longer circumferentially than said materialaccess way.

3. The combination of claim 1, wherein the cutter blocks, wedges andtheir respective aligned material access ways on the adjacent discs aredisposed in staggered relation along the drum.

References Cited in the file of this patent UNITED STATES PATENTS970,725 Kuhn Sept. 20, 1910 981,201 Kuhn Ian. 10, 1911 1,079,353 KuhnNOV. 25, 1913 1,175,071 Morgan Mar. 14, 1916 2,269,781 Osgood Jan. 13,1942 2,287,230 Cartlidge June 23, 1942

